freedombone/install-freedombone.sh

#!/bin/bash
# Freedombone install script intended for use with Debian Jessie

DOMAIN_NAME=$1
MY_USERNAME=$2

# Directory where source code is downloaded and compiled
INSTALL_DIR=/root/build

export DEBIAN_FRONTEND=noninteractive

function initial_setup {
  apt-get -y update
  apt-get -y dist-upgrade
  apt-get -y install ca-certificates emacs24
}

function install_editor {
  update-alternatives --set editor /usr/bin/emacs24
}

function enable_backports {
  echo "deb http://ftp.us.debian.org/debian jessie-backports main" >> /etc/apt/sources.list
}

function remove_proprietary_repos {
  sed -i 's/ non-free//g' /etc/apt/sources.list
}

function update_the_kernel {
  cd /opt/scripts/tools
  ./update_kernel.sh --kernel v3.15.10-bone7
}

function enable_zram {
  echo "options zram num_devices=1" >> /etc/modprobe.d/zram.conf
  echo "#!/bin/bash" > /etc/init.d/zram
  echo "### BEGIN INIT INFO" >> /etc/init.d/zram
  echo "# Provides: zram" >> /etc/init.d/zram
  echo "# Required-Start:" >> /etc/init.d/zram
  echo "# Required-Stop:" >> /etc/init.d/zram
  echo "# Default-Start: 2 3 4 5" >> /etc/init.d/zram
  echo "# Default-Stop: 0 1 6" >> /etc/init.d/zram
  echo "# Short-Description: Increased Performance In Linux With zRam (Virtual Swap Compressed in RAM)" >> /etc/init.d/zram
  echo "# Description: Adapted from systemd scripts at https://github.com/mystilleef/FedoraZram" >> /etc/init.d/zram
  echo "### END INIT INFO" >> /etc/init.d/zram
  echo "start() {" >> /etc/init.d/zram
  echo "    # get the number of CPUs" >> /etc/init.d/zram
  echo "    num_cpus=$(grep -c processor /proc/cpuinfo)" >> /etc/init.d/zram
  echo "    # if something goes wrong, assume we have 1" >> /etc/init.d/zram
  echo "    [ \"$num_cpus\" != 0 ] || num_cpus=1" >> /etc/init.d/zram
  echo "    # set decremented number of CPUs" >> /etc/init.d/zram
  echo "    decr_num_cpus=$((num_cpus - 1))" >> /etc/init.d/zram
  echo "    # get the amount of memory in the machine" >> /etc/init.d/zram
  echo "    mem_total_kb=$(grep MemTotal /proc/meminfo | grep -E --only-matching '[[:digit:]]+')" >> /etc/init.d/zram
  echo "    mem_total=$((mem_total_kb * 1024))" >> /etc/init.d/zram
  echo "    # load dependency modules" >> /etc/init.d/zram
  echo "    modprobe zram num_devices=$num_cpus" >> /etc/init.d/zram
  echo "    # initialize the devices" >> /etc/init.d/zram
  echo "    for i in $(seq 0 $decr_num_cpus); do" >> /etc/init.d/zram
  echo "    echo $((mem_total / num_cpus)) > /sys/block/zram$i/disksize" >> /etc/init.d/zram
  echo "    done" >> /etc/init.d/zram
  echo "    # Creating swap filesystems" >> /etc/init.d/zram
  echo "    for i in $(seq 0 $decr_num_cpus); do" >> /etc/init.d/zram
  echo "    mkswap /dev/zram$i" >> /etc/init.d/zram
  echo "    done" >> /etc/init.d/zram
  echo "    # Switch the swaps on" >> /etc/init.d/zram
  echo "    for i in $(seq 0 $decr_num_cpus); do" >> /etc/init.d/zram
  echo "    swapon -p 100 /dev/zram$i" >> /etc/init.d/zram
  echo "    done" >> /etc/init.d/zram
  echo "}" >> /etc/init.d/zram
  echo "stop() {" >> /etc/init.d/zram
  echo "    # get the number of CPUs" >> /etc/init.d/zram
  echo "    num_cpus=$(grep -c processor /proc/cpuinfo)" >> /etc/init.d/zram
  echo "    # set decremented number of CPUs" >> /etc/init.d/zram
  echo "    decr_num_cpus=$((num_cpus - 1))" >> /etc/init.d/zram
  echo "    # Switching off swap" >> /etc/init.d/zram
  echo "    for i in $(seq 0 $decr_num_cpus); do" >> /etc/init.d/zram
  echo "    if [ \"$(grep /dev/zram$i /proc/swaps)\" != \"\" ]; then" >> /etc/init.d/zram
  echo "    swapoff /dev/zram$i" >> /etc/init.d/zram
  echo "    sleep 1" >> /etc/init.d/zram
  echo "    fi" >> /etc/init.d/zram
  echo "    done" >> /etc/init.d/zram
  echo "    sleep 1" >> /etc/init.d/zram
  echo "    rmmod zram" >> /etc/init.d/zram
  echo "}" >> /etc/init.d/zram
  echo "case \"$1\" in" >> /etc/init.d/zram
  echo "    start)" >> /etc/init.d/zram
  echo "        start" >> /etc/init.d/zram
  echo "        ;;" >> /etc/init.d/zram
  echo "    stop)" >> /etc/init.d/zram
  echo "        stop" >> /etc/init.d/zram
  echo "        ;;" >> /etc/init.d/zram
  echo "    restart)" >> /etc/init.d/zram
  echo "        stop" >> /etc/init.d/zram
  echo "        sleep 3" >> /etc/init.d/zram
  echo "        start" >> /etc/init.d/zram
  echo "        ;;" >> /etc/init.d/zram
  echo "    *)" >> /etc/init.d/zram
  echo "        echo \"Usage: $0 {start|stop|restart}\"" >> /etc/init.d/zram
  echo "        RETVAL=1" >> /etc/init.d/zram
  echo "esac" >> /etc/init.d/zram
  echo "exit $RETVAL" >> /etc/init.d/zram
  chmod +x /etc/init.d/zram
  update-rc.d zram defaults
}

function hardware_random_number_generator
  apt-get -y install rng-tools
  sed -i 's|#HRNGDEVICE=/dev/hwrng|HRNGDEVICE=/dev/hwrng|g' /etc/default/rng-tools
  service rng-tools restart
}

function configure_ssh {
  sed -i 's/PermitRootLogin without-password/PermitRootLogin no/g' /etc/ssh/sshd_config
  sed -i 's/X11Forwarding yes/X11Forwarding no/g' /etc/ssh/sshd_config
  sed -i 's/ServerKeyBits 1024/ServerKeyBits 4096/g' /etc/ssh/sshd_config
  sed -i 's/TCPKeepAlive yes/TCPKeepAlive no/g' /etc/ssh/sshd_config
  sed -i 's|HostKey /etc/ssh/ssh_host_dsa_key|#HostKey /etc/ssh/ssh_host_dsa_key|g' /etc/ssh/sshd_config
  sed -i 's|HostKey /etc/ssh/ssh_host_ecdsa_key|#HostKey /etc/ssh/ssh_host_ecdsa_key|g' /etc/ssh/sshd_config
  echo "ClientAliveInterval 60" >> /etc/ssh/sshd_config
  echo "ClientAliveCountMax 3" >> /etc/ssh/sshd_config
  echo "Ciphers aes256-ctr,aes128-ctr" >> /etc/ssh/sshd_config
  echo "MACs hmac-sha2-512,hmac-sha2-256,hmac-ripemd160
  KexAlgorithms diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1,diffie-hellman-group-exchange-sha1" >> /etc/ssh/sshd_config
  service ssh restart
  apt-get -y install fail2ban
}

function regenerate_ssh_keys {
  rm -f /etc/ssh/ssh_host_*
  dpkg-reconfigure openssh-server
  service ssh restart
}

function set_your_domain_name {
  echo "$DOMAIN_NAME" > /etc/hostname
  hostname $DOMAIN_NAME
  echo "127.0.1.1  $DOMAIN_NAME" >> /etc/hosts
}

function time_synchronisation {
  apt-get -y install build-essential automake git pkg-config autoconf libtool libssl-dev
  apt-get -y remove ntpdate
  mkdir $INSTALL_DIR
  cd $INSTALL_DIR
  git clone https://github.com/ioerror/tlsdate.git
  cd $INSTALL_DIR/tlsdate
  ./autogen.sh
  ./configure
  make
  make install

  echo "#!/bin/bash" > /usr/bin/updatedate
  echo "TIMESOURCE=google.com" >> /usr/bin/updatedate
  echo "TIMESOURCE2=www.ptb.de" >> /usr/bin/updatedate
  echo "LOGFILE=/var/log/tlsdate.log" >> /usr/bin/updatedate
  echo "TIMEOUT=5" >> /usr/bin/updatedate
  echo "EMAIL=$MY_USERNAME@$DOMAIN_NAME" >> /usr/bin/updatedate
  echo "# File which contains the previous date as a number" >> /usr/bin/updatedate
  echo "BEFORE_DATE_FILE=/var/log/tlsdateprevious.txt" >> /usr/bin/updatedate
  echo "# File which contains the previous date as a string" >> /usr/bin/updatedate
  echo "BEFORE_FULLDATE_FILE=/var/log/tlsdate.txt" >> /usr/bin/updatedate
  echo "DATE_BEFORE=$(date)" >> /usr/bin/updatedate
  echo "BEFORE=$(date -d "$Y-$M-$D" '+%s')" >> /usr/bin/updatedate
  echo "BACKWARDS_BETWEEN=0" >> /usr/bin/updatedate
  echo "# If the date was previously set" >> /usr/bin/updatedate
  echo "if [[ -f \"$BEFORE_DATE_FILE\" ]]; then" >> /usr/bin/updatedate
  echo "    BEFORE_FILE=$(cat $BEFORE_DATE_FILE)" >> /usr/bin/updatedate
  echo "    BEFORE_FULLDATE=$(cat $BEFORE_FULLDATE_FILE)" >> /usr/bin/updatedate
  echo "    # is the date going backwards?" >> /usr/bin/updatedate
  echo "    if (( BEFORE_FILE > BEFORE )); then" >> /usr/bin/updatedate
  echo "        echo -n \"Date went backwards between tlsdate updates. \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "        echo -n \"$BEFORE_FILE > $BEFORE, \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "        echo \"$BEFORE_FULLDATE > $DATE_BEFORE\" >> $LOGFILE" >> /usr/bin/updatedate
  echo "        # Send a warning email" > /usr/bin/updatedate
  echo "        echo $(tail $LOGFILE -n 2) | mail -s \"tlsdate anomaly\" $EMAIL" >> /usr/bin/updatedate
  echo "        # Try another time source" >> /usr/bin/updatedate
  echo "        TIMESOURCE=$TIMESOURCE2" >> /usr/bin/updatedate
  echo "        # try running without any parameters" >> /usr/bin/updatedate
  echo "        tlsdate >> $LOGFILE" >> /usr/bin/updatedate
  echo "        BACKWARDS_BETWEEN=1" >> /usr/bin/updatedate
  echo "    fi" >> /usr/bin/updatedate
  echo "fi" >> /usr/bin/updatedate
  echo "# Set the date" >> /usr/bin/updatedate
  echo "/usr/bin/timeout $TIMEOUT tlsdate -l -t -H $TIMESOURCE -p 443 >> $LOGFILE" >> /usr/bin/updatedate
  echo "DATE_AFTER=$(date)" >> /usr/bin/updatedate
  echo "AFTER=$(date -d "$Y-$M-$D" '+%s')" >> /usr/bin/updatedate
  echo "# After setting the date did it go backwards?" >> /usr/bin/updatedate
  echo "if (( AFTER < BEFORE )); then" >> /usr/bin/updatedate
  echo "    echo \"Incorrect date: $DATE_BEFORE -> $DATE_AFTER\" >> $LOGFILE" >> /usr/bin/updatedate
  echo "    # Send a warning email" >> /usr/bin/updatedate
  echo "    echo $(tail $LOGFILE -n 2) | mail -s \"tlsdate anomaly\" $EMAIL" >> /usr/bin/updatedate
  echo "    # Try resetting the date from another time source" >> /usr/bin/updatedate
  echo "    /usr/bin/timeout $TIMEOUT tlsdate -l -t -H $TIMESOURCE2 -p 443 >> $LOGFILE" >> /usr/bin/updatedate
  echo "    DATE_AFTER=$(date)" >> /usr/bin/updatedate
  echo "    AFTER=$(date -d "$Y-$M-$D" '+%s')" >> /usr/bin/updatedate
  echo "else" >> /usr/bin/updatedate
  echo "    echo -n $TIMESOURCE >> $LOGFILE" >> /usr/bin/updatedate
  echo "    if [[ -f \"$BEFORE_DATE_FILE\" ]]; then" >> /usr/bin/updatedate
  echo "        echo -n \" \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "        echo -n $BEFORE_FILE >> $LOGFILE" >> /usr/bin/updatedate
  echo "    fi" >> /usr/bin/updatedate
  echo "    echo -n \" \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "    echo -n $BEFORE >> $LOGFILE" >> /usr/bin/updatedate
  echo "    echo -n \" \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "    echo -n $AFTER >> $LOGFILE" >> /usr/bin/updatedate
  echo "    echo -n \" \" >> $LOGFILE" >> /usr/bin/updatedate
  echo "    echo $DATE_AFTER >> $LOGFILE" >> /usr/bin/updatedate
  echo "fi" >> /usr/bin/updatedate
  echo "# Log the last date" >> /usr/bin/updatedate
  echo "if [ BACKWARDS_BETWEEN == 0 ]; then" >> /usr/bin/updatedate
  echo "    echo \"$AFTER\" > $BEFORE_DATE_FILE" >> /usr/bin/updatedate
  echo "    echo \"$DATE_AFTER\" > $BEFORE_FULLDATE_FILE" >> /usr/bin/updatedate
  echo "    exit 0" >> /usr/bin/updatedate
  echo "else" >> /usr/bin/updatedate
  echo "    exit 1" >> /usr/bin/updatedate
  echo "fi" >> /usr/bin/updatedate
  chmod +x /usr/bin/updatedate
  echo "*/15           * *   *   *   root /usr/bin/updatedate" >> /etc/crontab
  service cron restart

  echo "#!/bin/bash" > /etc/init.d/tlsdate
  echo "# /etc/init.d/tlsdate" >> /etc/init.d/tlsdate
  echo "### BEGIN INIT INFO" >> /etc/init.d/tlsdate
  echo "# Provides:          tlsdate" >> /etc/init.d/tlsdate
  echo "# Required-Start:    $remote_fs $syslog" >> /etc/init.d/tlsdate
  echo "# Required-Stop:     $remote_fs $syslog" >> /etc/init.d/tlsdate
  echo "# Default-Start:     2 3 4 5" >> /etc/init.d/tlsdate
  echo "# Default-Stop:      0 1 6" >> /etc/init.d/tlsdate
  echo "# Short-Description: Initially calls tlsdate with the timewarp option" >> /etc/init.d/tlsdate
  echo "# Description:       Initially calls tlsdate with the timewarp option" >> /etc/init.d/tlsdate
  echo "### END INIT INFO" >> /etc/init.d/tlsdate
  echo "# Author: Bob Mottram <bob@robotics.uk.to>" >> /etc/init.d/tlsdate
  echo "PATH='/usr/local/sbin:/usr/local/bin:/usr/bin:/sbin:/usr/sbin:/bin'" >> /etc/init.d/tlsdate
  echo "LOGFILE=\"/var/log/tlsdate.log\"" >> /etc/init.d/tlsdate
  echo "TLSDATECOMMAND=\"tlsdate --timewarp -l -H www.ptb.de -p 443 >> $LOGFILE\"" >> /etc/init.d/tlsdate
  echo "#Start-Stop here" >> /etc/init.d/tlsdate
  echo "case "$1" in" >> /etc/init.d/tlsdate
  echo "  start)" >> /etc/init.d/tlsdate
  echo "    echo "tlsdate started"" >> /etc/init.d/tlsdate
  echo "    $TLSDATECOMMAND" >> /etc/init.d/tlsdate
  echo "    ;;" >> /etc/init.d/tlsdate
  echo "  stop)" >> /etc/init.d/tlsdate
  echo "    echo "tlsdate stopped"" >> /etc/init.d/tlsdate
  echo "    ;;" >> /etc/init.d/tlsdate
  echo "  restart)" >> /etc/init.d/tlsdate
  echo "    echo "tlsdate restarted"" >> /etc/init.d/tlsdate
  echo "    $TLSDATECOMMAND" >> /etc/init.d/tlsdate
  echo "    ;;" >> /etc/init.d/tlsdate
  echo "    *)" >> /etc/init.d/tlsdate
  echo "  echo "Usage: $0 {start|stop|restart}"" >> /etc/init.d/tlsdate
  echo "  exit 1" >> /etc/init.d/tlsdate
  echo "  ;;" >> /etc/init.d/tlsdate
  echo "esac" >> /etc/init.d/tlsdate
  echo "exit 0" >> /etc/init.d/tlsdate
  chmod +x /etc/init.d/tlsdate
  update-rc.d tlsdate defaults
}

function defend_against_port_scanning
  apt-get -y install portsentry
}

function configure_firewall {
  iptables -P INPUT ACCEPT
  ip6tables -P INPUT ACCEPT
  iptables -F
  ip6tables -F
  iptables -X
  ip6tables -X
  iptables -P INPUT DROP
  ip6tables -P INPUT DROP
}

function configure_firewall_for_email {
  iptables -A INPUT -i eth0 -p tcp --dport 22 -j ACCEPT
  iptables -A INPUT -i eth0 -p tcp --dport 25 -j ACCEPT
  iptables -A INPUT -i eth0 -p tcp --dport 587 -j ACCEPT
  iptables -A INPUT -i eth0 -p tcp --dport 465 -j ACCEPT
  iptables -A INPUT -i eth0 -p tcp --dport 993 -j ACCEPT
}

function save_firewall_settings {
	# TODO
}

function configure_internet_protocol {
  sed -i "s/#net.ipv4.tcp_syncookies=1/net.ipv4.tcp_syncookies=1/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.conf.all.accept_redirects = 0/net.ipv4.conf.all.accept_redirects = 0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv6.conf.all.accept_redirects = 0/net.ipv6.conf.all.accept_redirects = 0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.conf.all.send_redirects = 0/net.ipv4.conf.all.send_redirects = 0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.conf.all.accept_source_route = 0/net.ipv4.conf.all.accept_source_route = 0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv6.conf.all.accept_source_route = 0/net.ipv6.conf.all.accept_source_route = 0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.conf.default.rp_filter=1/net.ipv4.conf.default.rp_filter=1/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.conf.all.rp_filter=1/net.ipv4.conf.all.rp_filter=1/g" /etc/sysctl.conf
  sed -i "s/#net.ipv4.ip_forward=1/net.ipv4.ip_forward=0/g" /etc/sysctl.conf
  sed -i "s/#net.ipv6.conf.all.forwarding=1/net.ipv6.conf.all.forwarding=0/g" /etc/sysctl.conf
  echo "# ignore pings" >> /etc/sysctl.conf
  echo "net.ipv4.icmp_echo_ignore_all = 1" >> /etc/sysctl.conf
  echo "net.ipv6.icmp_echo_ignore_all = 1" >> /etc/sysctl.conf
  echo "# disable ipv6" >> /etc/sysctl.conf
  echo "net.ipv6.conf.all.disable_ipv6 = 1" >> /etc/sysctl.conf
  echo "net.ipv4.tcp_synack_retries = 2" >> /etc/sysctl.conf
  echo "net.ipv4.tcp_syn_retries = 1" >> /etc/sysctl.conf
  echo "# keepalive" >> /etc/sysctl.conf
  echo "net.ipv4.tcp_keepalive_probes = 9" >> /etc/sysctl.conf
  echo "net.ipv4.tcp_keepalive_intvl = 75" >> /etc/sysctl.conf
  echo "net.ipv4.tcp_keepalive_time = 7200" >> /etc/sysctl.conf
}

function script_to_make_self_signed_certificates {
  echo "#!/bin/bash" > /usr/bin/makecert
  echo "HOSTNAME=$1" >> /usr/bin/makecert
  echo "COUNTRY_CODE=\"US\"" >> /usr/bin/makecert
  echo "AREA=\"Free Speech Zone\"" >> /usr/bin/makecert
  echo "LOCATION=\"Freedomville\"" >> /usr/bin/makecert
  echo "ORGANISATION=\"Freedombone\"" >> /usr/bin/makecert
  echo "UNIT=\"Freedombone Unit\"" >> /usr/bin/makecert
  echo "if ! which openssl > /dev/null ;then" >> /usr/bin/makecert
  echo "    echo "$0: openssl is not installed, exiting" 1>&2" >> /usr/bin/makecert
  echo "    exit 1" >> /usr/bin/makecert
  echo "fi" >> /usr/bin/makecert
  echo "openssl req -x509 -nodes -days 3650 -sha256 -subj \"/O=$ORGANISATION/OU=$UNIT/C=$COUNTRY_CODE/ST=$AREA/L=$LOCATION/CN=$HOSTNAME\" -newkey rsa:4096 -keyout /etc/ssl/private/$HOSTNAME.key -out /etc/ssl/certs/$HOSTNAME.crt" >> /usr/bin/makecert
  echo "openssl dhparam -check -text -5 1024 -out /etc/ssl/certs/$HOSTNAME.dhparam" >> /usr/bin/makecert
  echo "chmod 400 /etc/ssl/private/$HOSTNAME.key" >> /usr/bin/makecert
  echo "chmod 640 /etc/ssl/certs/$HOSTNAME.crt" >> /usr/bin/makecert
  echo "chmod 640 /etc/ssl/certs/$HOSTNAME.dhparam" >> /usr/bin/makecert
  echo "/etc/init.d/nginx reload" >> /usr/bin/makecert
  echo "# add the public certificate to a separate directory" >> /usr/bin/makecert
  echo "# so that we can redistribute it easily" >> /usr/bin/makecert
  echo "if [ ! -d /etc/ssl/mycerts ]; then" >> /usr/bin/makecert
  echo "  mkdir /etc/ssl/mycerts" >> /usr/bin/makecert
  echo "fi" >> /usr/bin/makecert
  echo "cp /etc/ssl/certs/$HOSTNAME.crt /etc/ssl/mycerts" >> /usr/bin/makecert
  echo "# Create a bundle of your certificates" >> /usr/bin/makecert
  echo "cat /etc/ssl/mycerts/*.crt > /etc/ssl/freedombone-bundle.crt" >> /usr/bin/makecert
  echo "tar -czvf /etc/ssl/freedombone-certs.tar.gz /etc/ssl/mycerts/*.crt" >> /usr/bin/makecert
  chmod +x /usr/bin/makecert
}

function configure_email {
  apt-get -y remove postfix
  apt-get -y install exim4 sasl2-bin swaks libnet-ssleay-perl procmail
  echo "dc_eximconfig_configtype='internet'" > /etc/exim4/update-exim4.conf.conf
  echo "dc_other_hostnames='$DOMAIN_NAME'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_local_interfaces=''" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_readhost=''" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_relay_domains=''" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_minimaldns='false'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_relay_nets='192.168.1.0/24'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_smarthost=''" >> /etc/exim4/update-exim4.conf.conf
  echo "CFILEMODE='644'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_use_split_config='false'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_hide_mailname=''" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_mailname_in_oh='true'" >> /etc/exim4/update-exim4.conf.conf
  echo "dc_localdelivery='maildir_home'" >> /etc/exim4/update-exim4.conf.conf
  update-exim4.conf
  sed -i "s/START=no/START=yes/g" /etc/default/saslauthd
  /etc/init.d/saslauthd start

  # make a tls certificate for email
  makecert exim
  mv /etc/ssl/private/exim.key /etc/exim4
  mv /etc/ssl/certs/exim.crt /etc/exim4
  mv /etc/ssl/certs/exim.dhparam /etc/exim4
  chown root:Debian-exim /etc/exim4/exim.key /etc/exim4/exim.crt /etc/exim4/exim.dhparam
  chmod 640 /etc/exim4/exim.key /etc/exim4/exim.crt /etc/exim4/exim.dhparam

  sed -i '/login_saslauthd_server/,/.endif/ s/# *//' /etc/exim4/exim4.conf.template
  sed -i '/.ifdef MAIN_HARDCODE_PRIMARY_HOSTNAME/i\MAIN_HARDCODE_PRIMARY_HOSTNAME = $DOMAIN_NAME\nMAIN_TLS_ENABLE = true' /etc/exim4/exim4.conf.template
  sed -i "s|SMTPLISTENEROPTIONS=''|SMTPLISTENEROPTIONS='-oX 465:25:587 -oP /var/run/exim4/exim.pid'|g" /etc/default/exim4
  sed -i '/03_exim4-config_tlsoptions/a\tls_on_connect_ports=465' /etc/exim4/exim4.conf.template

  adduser $MY_USERNAME sasl
  addgroup Debian-exim sasl
  /etc/init.d/exim4 restart
  mkdir -m 700 /etc/skel/Maildir
  mkdir -m 700 /etc/skel/Maildir/Sent
  mkdir -m 700 /etc/skel/Maildir/Sent/tmp
  mkdir -m 700 /etc/skel/Maildir/Sent/cur
  mkdir -m 700 /etc/skel/Maildir/Sent/new
  mkdir -m 700 /etc/skel/Maildir/.learn-spam
  mkdir -m 700 /etc/skel/Maildir/.learn-spam/cur
  mkdir -m 700 /etc/skel/Maildir/.learn-spam/new
  mkdir -m 700 /etc/skel/Maildir/.learn-spam/tmp
  mkdir -m 700 /etc/skel/Maildir/.learn-ham
  mkdir -m 700 /etc/skel/Maildir/.learn-ham/cur
  mkdir -m 700 /etc/skel/Maildir/.learn-ham/new
  mkdir -m 700 /etc/skel/Maildir/.learn-ham/tmp
  ln -s /etc/skel/Maildir/.learn-spam /etc/skel/Maildir/spam
  ln -s /etc/skel/Maildir/.learn-ham /etc/skel/Maildir/ham

  if [ ! -d /home/$MY_USERNAME/Maildir ]; then
    mkdir -m 700 /home/$MY_USERNAME/Maildir
    mkdir -m 700 /home/$MY_USERNAME/Maildir/cur
    mkdir -m 700 /home/$MY_USERNAME/Maildir/tmp
    mkdir -m 700 /home/$MY_USERNAME/Maildir/new
    mkdir -m 700 /home/$MY_USERNAME/Maildir/Sent
    mkdir -m 700 /home/$MY_USERNAME/Maildir/Sent/cur
	mkdir -m 700 /home/$MY_USERNAME/Maildir/Sent/tmp
	mkdir -m 700 /home/$MY_USERNAME/Maildir/Sent/new
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-spam
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-spam/cur
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-spam/new
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-spam/tmp
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-ham
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-ham/cur
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-ham/new
	mkdir -m 700 /home/$MY_USERNAME/Maildir/.learn-ham/tmp
	ln -s /home/$MY_USERNAME/Maildir/.learn-spam /home/$MY_USERNAME/Maildir/spam
	ln -s /home/$MY_USERNAME/Maildir/.learn-ham /home/$MY_USERNAME/Maildir/ham
	chown -R $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/Maildir
  fi
}

function spam_filtering {
  apt-get -y install spamassassin exim4-daemon-heavy
  sed -i 's/ENABLED=0/ENABLED=1/g' /etc/default/spamassassin
  sed -i 's/# spamd_address = 127.0.0.1 783/spamd_address = 127.0.0.1 783/g' /etc/exim4/exim4.conf.template
  # This configuration is based on https://wiki.debian.org/DebianSpamAssassin
  sed -i 's/local_parts = postmaster/local_parts = postmaster:abuse/g' /etc/exim4/conf.d/acl/30_exim4-config_check_rcpt
  sed -i '/domains = +local_domains : +relay_to_domains/a\    set acl_m0 = rfcnames' /etc/exim4/conf.d/acl/30_exim4-config_check_rcpt
  sed -i 's/accept/accept condition = ${if eq{$acl_m0}{rfcnames} {1}{0}}/g' /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "warn  message = X-Spam-Score: $spam_score ($spam_bar)" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "      spam = nobody:true" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "warn  message = X-Spam-Flag: YES" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "      spam = nobody" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "warn  message = X-Spam-Report: $spam_report" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "      spam = nobody" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "# reject spam at high scores (> 12)" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "deny  message = This message scored $spam_score spam points." >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "      spam = nobody:true" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  echo "      condition = ${if >{$spam_score_int}{120}{1}{0}}" >> /etc/exim4/conf.d/acl/40_exim4-config_check_data
  # procmail configuration
  echo "MAILDIR=$HOME/Maildir" > /home/$MY_USERNAME/.procmailrc
  echo "DEFAULT=$MAILDIR/" >> /home/$MY_USERNAME/.procmailrc
  echo "LOGFILE=$HOME/log/procmail.log" >> /home/$MY_USERNAME/.procmailrc
  echo "LOGABSTRACT=all" >> /home/$MY_USERNAME/.procmailrc
  echo "# get spamassassin to check emails" >> /home/$MY_USERNAME/.procmailrc
  echo ":0fw: .spamassassin.lock" >> /home/$MY_USERNAME/.procmailrc
  echo "  * < 256000" >> /home/$MY_USERNAME/.procmailrc
  echo "| spamc" >> /home/$MY_USERNAME/.procmailrc
  echo "# strong spam are discarded" >> /home/$MY_USERNAME/.procmailrc
  echo ":0" >> /home/$MY_USERNAME/.procmailrc
  echo "  * ^X-Spam-Level: \*\*\*\*\*\*" >> /home/$MY_USERNAME/.procmailrc
  echo "/dev/null" >> /home/$MY_USERNAME/.procmailrc
  echo "# weak spam are kept just in case - clear this out every now and then" >> /home/$MY_USERNAME/.procmailrc
  echo ":0" >> /home/$MY_USERNAME/.procmailrc
  echo "  * ^X-Spam-Level: \*\*\*\*\*" >> /home/$MY_USERNAME/.procmailrc
  echo ".0-spam/" >> /home/$MY_USERNAME/.procmailrc
  echo "# otherwise, marginal spam goes here for revision" >> /home/$MY_USERNAME/.procmailrc
  echo ":0" >> /home/$MY_USERNAME/.procmailrc
  echo "  * ^X-Spam-Level: \*\*" >> /home/$MY_USERNAME/.procmailrc
  echo ".spam/" >> /home/$MY_USERNAME/.procmailrc
  chown $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/.procmailrc
  # filtering scripts
  echo "#!/bin/bash" > /usr/bin/filterspam
  echo "USERNAME=$1" >> /usr/bin/filterspam
  echo "MAILDIR=/home/$USERNAME/Maildir/.learn-spam" >> /usr/bin/filterspam
  echo "if [ ! -d \"$MAILDIR\" ]; then" >> /usr/bin/filterspam
  echo "    exit" >> /usr/bin/filterspam
  echo "fi" >> /usr/bin/filterspam
  echo "for f in `ls $MAILDIR/cur`" >> /usr/bin/filterspam
  echo "do" >> /usr/bin/filterspam
  echo "    spamc -L spam < \"$MAILDIR/cur/$f\" > /dev/null" >> /usr/bin/filterspam
  echo "    rm \"$MAILDIR/cur/$f\"" >> /usr/bin/filterspam
  echo "done" >> /usr/bin/filterspam
  echo "for f in `ls $MAILDIR/new`" >> /usr/bin/filterspam
  echo "do" >> /usr/bin/filterspam
  echo "    spamc -L spam < \"$MAILDIR/new/$f\" > /dev/null" >> /usr/bin/filterspam
  echo "    rm \"$MAILDIR/new/$f\"" >> /usr/bin/filterspam
  echo "done" >> /usr/bin/filterspam

  echo "#!/bin/bash" > /usr/bin/filterham
  echo "USERNAME=$1" >> /usr/bin/filterham
  echo "MAILDIR=/home/$USERNAME/Maildir/.learn-ham" >> /usr/bin/filterham
  echo "if [ ! -d \"$MAILDIR\" ]; then" >> /usr/bin/filterham
  echo "    exit" >> /usr/bin/filterham
  echo "fi" >> /usr/bin/filterham
  echo "for f in `ls $MAILDIR/cur`" >> /usr/bin/filterham
  echo "do" >> /usr/bin/filterham
  echo "    spamc -L ham < \"$MAILDIR/cur/$f\" > /dev/null" >> /usr/bin/filterham
  echo "    rm \"$MAILDIR/cur/$f\"" >> /usr/bin/filterham
  echo "done" >> /usr/bin/filterham
  echo "for f in `ls $MAILDIR/new`" >> /usr/bin/filterham
  echo "do" >> /usr/bin/filterham
  echo "    spamc -L ham < \"$MAILDIR/new/$f\" > /dev/null" >> /usr/bin/filterham
  echo "    rm \"$MAILDIR/new/$f\"" >> /usr/bin/filterham
  echo "done" >> /usr/bin/filterham

  echo "*/3 * * * * root /usr/bin/timeout 120 /usr/bin/filterspam $MY_USERNAME" >> /etc/crontab
  echo "*/3 * * * * root /usr/bin/timeout 120 /usr/bin/filterham $MY_USERNAME" >> /etc/crontab
  chmod 655 /usr/bin/filterspam /usr/bin/filterham
  service spamassassin restart
  service exim4 restart
  service cron restart
}

function configure_imap {
  apt-get -y install dovecot-common dovecot-imapd
  makecert dovecot
  chown root:dovecot /etc/ssl/certs/dovecot.crt
  chown root:dovecot /etc/ssl/private/dovecot.key
  chown root:dovecot /etc/ssl/private/dovecot.dhparams

  sed -i 's|#ssl = yes|ssl = yes|g' /etc/dovecot/conf.d/10-ssl.conf
  sed -i 's|ssl_cert = </etc/dovecot/dovecot.pem|ssl_cert = </etc/ssl/certs/dovecot.crt|g' /etc/dovecot/conf.d/10-ssl.conf
  sed -i 's|ssl_key = </etc/dovecot/private/dovecot.pem|/etc/ssl/private/dovecot.key|g' /etc/dovecot/conf.d/10-ssl.conf
  sed -i 's|#ssl_dh_parameters_length = 1024|ssl_dh_parameters_length = 1024|g' /etc/dovecot/conf.d/10-ssl.conf
  sed -i 's/#ssl_prefer_server_ciphers = no/ssl_prefer_server_ciphers = yes/g' /etc/dovecot/conf.d/10-ssl.conf
  echo "ssl_cipher_list = 'EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA384:EECDH+aRSA+SHA256:EECDH:+CAMELLIA256:+AES256:+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!ECDSA:CAMELLIA256-SHA:AES256-SHA:CAMELLIA128-SHA:AES128-SHA'" >> /etc/dovecot/conf.d/10-ssl.conf


  sed -i 's/#listen = *, ::/listen = */g' /etc/dovecot/dovecot.conf
  sed -i 's/#disable_plaintext_auth = yes/disable_plaintext_auth = no/g' /etc/dovecot/conf.d/10-auth.conf
  sed -i 's/auth_mechanisms = plain/auth_mechanisms = plain login/g' /etc/dovecot/conf.d/10-auth.conf
  sed -i 's|#   mail_location = maildir:~/Maildir|   mail_location = maildir:~/Maildir:LAYOUT=fs|g' /etc/dovecot/conf.d/10-mail.conf
}

function configure_gpg {
  apt-get -y install gnupg
}

initial_setup
install_editor
enable_backports
remove_proprietary_repos
update_the_kernel
enable_zram
hardware_random_number_generator
configure_ssh
regenerate_ssh_keys
set_your_domain_name
time_synchronisation
defend_against_port_scanning
configure_firewall
configure_firewall_for_email
save_firewall_settings
configure_internet_protocol
script_to_make_self_signed_certificates
configure_email
spam_filtering
configure_imap
configure_gpg